As far as pragmatic uses, many people on my forums make threads for a specific project. Often, they like posting news at the end as they go, and keeping the first post updated with the most recent information/downloads, etc. To have to view the thread first, and only then be able to click the first page is unintuitive.
I'd suggest having the thread title as normal, having pages listed (so if they want to view the last page, they just click "Last"), and having the star or whatever take them to the first post that is not marked as read by the user clicking. The star should not be available for guests.